The term “polygraph” literally means “many writings.” The name refers to the manner in which selected physiological activities are simultaneously recorded. Polygraph examiners my use conventional instruments, sometimes referred to analog instruments, or computerized instruments. It is important to understand what a polygraph examination entails. A polygraph will collect physiological data from at least three systems in the body. Polygraph admissibility varies from jurisdiction to jurisdiction. Some states ban it completely; others allow results by stipulation; and some allow polygraph evidence over objection.